The father of a four-year-old boy killed while holding his hand in a horror crash told witnesses he blamed himself for the accident.
Three pedestrians, including the boy, were struck by an out-of-control Toyota LandCruiser outside a medical centre at Berwick, in Melbourne's east.
A couple who had been driving behind the 4WD and tried to help save the child's life said the father told them it was his fault as they tried in vain to save the boy's life.
Bystanders have alleged the 56-year-old driver had been receiving dialysis treatment at nearby Casey Hospital prior to the crash, said the Daily Mail.
Authorities are investigation whether the driver from Pakenham fainted or became disoriented prior to the crash.
"I remember the dad saying "it's my fault". It's not his fault," witness Sarah Smith said through tears.
Cameron and Sarah Smith were driving behind the LandCruiser when the crash happened and rushed to assist.
"He was in front of us and he started to veer off into oncoming traffic and he's gone airborne," Mr Smith said.
Detective Sergeant Mark Amos said the vehicle was travelling along Kangan Drive towards Clyde Road around midday when it careered over a median strip into the car park of the Epworth Specialist Centre in Berwick,
"As he was negotiating a left-hand bend, the driver for some reason failed to take the bend," he said, according to the ABC.
"On entering that car park, he struck a small child pedestrian who was walking with his father, then that land cruiser has come to rest next to some parked cars."
"Unfortunately as a result of that collision, the young child has died whilst trying to be saved and taken to hospital by air.
"The father's gone out with his son, holding his hand, doing what good dads do and this outcome's come up on them very, very suddenly."
Meanwhile, a couple who had been driving behind the 4WD were "absolutely hysterical" when they were told that the little boy they tried to save had died.
Cameron and Sarah Smith had stopped to help the boy and console his father after the child and two other adults were struck.
"I remember the dad saying "it's my fault". It's not his fault," Ms Smith said through tears.
Ten News reporter Katherine Firkin said the woman fell to the ground when she heard the news and her husband tried to console her.
'It was pretty dramatic and pretty horrendous,' Ms Firkin told news.com.au.
'The woman said she had children of her own, she was shaking and crying and couldn't believe something like this happened in broad daylight standing outside a medical centre,' Ms Firkin said.
Photos taken at the scene show the Toyota LandCruiser on its side with a smashed windscreen, next to a number of damaged parked cars.
A Victoria Ambulance spokesman said paramedics were called to the scene in Kangan Drive just before midday.